Defense of territories by rutting red deer stags, Cervus elaphus, in Patagonia, Argentina

SMITH-FLUECK, JM; FLUCK, WT

Advances in deer biology

Bartos, L. et al., Research Institute of Animal Production

Lugar: Praha, Czech Rep.; Año: 2006; p. 174 - 178

Mating behavior of Old and New World Cervus elaphus males has generally been characterized as mobile harem defense. Intraspecific variation in red deer mating systems among prime males has only been described for a southern Iberia population, where territorial defense and mobile-harem-defense behaviors were shown to coexist. Resource distribution might be a factor indirectly influencing the choice of mating systems. It has been hypothesized that male territoriality should arise during the rut where resources are scarce and patchy. This study was a first to evaluate the mating strategies employed by breeding stags of the Andean-Patagonian cordillera, during a time of the year when forage availability is at its lowest and more patchily distributed across the landscape. Evidence was found for prime males defending territories 0.8 to 2.5 ha in size; these males reacted aggressively to other males even in absence of females within their territory. Although frequency of a male’s aggressive interactions towards other males was not affected by the number of females in his harem, his frequency of interactions with females positively correlated with number of females in the harem (rS = 0.50, n = 37, p = 0.002). Territory boundaries established by focal males shifted temporally and number of territorial males in mallin at any one time varied from 0 to 6. Only males of larger body and antler mass held territories (n=13) around the peak of rut. Evidence of mobile harem defense was not found in the habitats monitored; instead, territorial defense, in open “mallin” habitat receiving high female concentrations, was the strategy of choice by the prime breeding males.  Non-prime males exhibited various other semblances of mating strategies, including adopting territories of prime males after these had left. The heterogeneous landscape allowed females to use various habitat types during the rut. Their movement patterns in turn influenced the strategies selected by the males.